--- title: "Japan Will Arm Its Submarines With Long-Range Cruise Missiles" description: "Japan continues to work toward enhancing its [long-range cruise missile capability](), with contracts issued for a new standoff capability for its submarine fleet, as well as improved anti-ship missiles for its destroyers. Contracts have now been issued for the mass…" date: "2025-10-09" modified: "2025-10-09" authors: - name: "Thomas Newdick" job_title: "Staff Writer" link: "https://www.twz.com/authors/thomas-newdick" url: "https://www.twz.com/sea/japan-will-arm-its-submarines-with-long-range-cruise-missiles" categories: - "Anti-Ship Cruise Missile" - "Around The Globe" - "Diesel-Electric Submarines" - "Indo-Pacific" - "Japan" - "Japan Maritime Self Defense Force" - "Land Attack Cruise Missiles" - "Naval Munitions" - "Navies" - "News & Features" - "R/UGM-109 Tomahawk" - "Sea" - "Submarines" --- # Japan Will Arm Its Submarines With Long-Range Cruise Missiles ![Japan Maritime Self-Defense Force Oyashio-class submarine JS Mocishio transits with ships assigned to Rim of the Pacific 2010 combined task force as part of a photo exercise noerth of Hawaii. RIMPAC, the world’s largest multinational maritime exercise is a biennial event which allows participating nations to work together to build trust and enhance partnerships needed to improve maritime security.]() *U.S. Navy* Japan continues to work toward enhancing its [long-range cruise missile capability](), with contracts issued for a new standoff capability for its submarine fleet, as well as improved anti-ship missiles for its destroyers. Contracts have now been issued for the mass production of both those weapons, which come as the country bolsters its abilities to attack both land targets and enemy surface warships, to counter the growing threats from [China]() and [North Korea](), in particular. Japan’s Ministry of Defense [announced]() the new contracts for the upgraded ship-launched Type 12 anti-ship missile and the unnamed torpedo-tube-launched cruise missile for submarines on Tuesday. Both contracts were awarded to Mitsubishi Heavy Industries (MHI). ![]() *Test-firing of a Japan Ground Self-Defense Forces baseline Type 12 anti-ship missile. *JGSDF** In a statement, Japan’s Ministry of Defense said the contracts were part of “strengthening \[…\] standoff defense capabilities in order to intercept and eliminate invading forces against Japan at an early stage and at a long distance.” The ministry said it was “currently working to acquire domestically produced standoff missiles as soon as possible.” The ministry today published its [defense white paper](), which further outlined its standoff defense capability, which is one of the core pillars of its modernization program. According to the white paper, “Japan will acquire capabilities to deal with vessels and landing forces invading Japan, including its remote islands, from locations outside of threat zones.” As part of this, the paper calls for continued development of the upgraded Type 12, aiming to complete development of the ship-launched version of the missile by the end of Japan’s fiscal year 2026. Japanese fiscal years run from April 1 to March 31. The defense white paper also specifies the “Buildup \[of\] submarine-type standoff defense capabilities that can be launched from submarines that can operate in a highly covert manner.” Details about the submarine-launched missile remain strictly limited, but reports that Japan was considering introducing such a capability to its existing [submarine fleet](), or future submarines, emerged back in 2021, [as we discussed at the time](). https://twitter.com/show\_murano/status/1476358856800358409?ref\_src=twsrc%5Etfw%7Ctwcamp%5Etweetembed%7Ctwterm%5E1476358856800358409%7Ctwgr%5E5f94d5ce77f01c9ca3a7eaaa6249482e373e92ce%7Ctwcon%5Es1\_c10&ref\_url=https%3A%2F%2Fwww.twz.com%2F43683%2Fjapan-wants-to-arm-its-submarines-with-long-range-cruise-missiles-report Back then, it was reported that the missile would have a range of over 620 miles and would be fielded from the latter half of the 2020s. In terms of its mission, the submarine-launched missile will provide the Japan Maritime Self-Defense Force (JMSDF) with a new standoff capability to attack both targets on land and as well as enemy surface warships. While the type of missile and even its name remain unknown, previous reports suggested it would be based on the Type 12. This is a subsonic anti-ship missile, the first version of which entered service with the Japan Ground Self-Defense Force (JGSDF), and which has a range of around 124 miles. ***The Type 12 ground-launched anti-ship missile:*** https://www.youtube.com/watch?v=-W7RTW\_xP1s The fact that the contract was issued to MHI, at the same time as a contract for an improved ship-launched version of the Type 12, suggests that the sub-launched weapon may be a Type 12 derivative, too. There had been previous discussions about the JMSDF considering firing the sub-launched missile from either a [vertical launch system]() (VLS) or torpedo tubes. Based on the requirement to get the missile into service as soon as possible, the tube-launched version makes sense, since the JMSDF does not currently have any submarine-based VLS in service. An earlier [report]() from the *Yomiuri Shimbun* newspaper said that the JMSDF would first arm its submarines with an anti-ship version of the missile, before introducing a version with a land-attack capability. ![POLARIS POINT, Guam (June 10, 2018) - A Japan Maritime Self-Defense Force submarine JS Soryu (SS-501) is pulled away from the submarine tender USS Frank Cable (AS 40) after a touch-and-go exercise, June 10. Frank Cable, forward-deployed to Guam, repairs, rearms and reprovisions deployed U.S. Naval Forces in the Indo-Pacific region. (U.S. Navy photo by Mass Communication Specialist 3rd Class Randall W. Ramaswamy/Released)]() *The JMSDF submarine *Soryu* is pulled away from the submarine tender USS *Frank Cable* while operating in Guam. *U.S. Navy photo by Mass Communication Specialist 3rd Class Randall W. Ramaswamy/Released* Petty Officer 2nd Class Randall Ramaswamy* Currently, JMSDF submarines are armed with [Harpoon anti-ship missiles]() that are launched from standard torpedo tubes. However, they have a much shorter range than the new weapon and don’t have a land-attack capability. [The latest]() UGM-84L Harpoon Block II in JMSDF service can hit targets at a distance of around 80 miles. With that in mind, a long-range cruise missile for its submarine fleet will be a big deal for the JMSDF and one that can rapidly add to the country’s broader strike capabilities. Currently, the JMSDF operates a frontline fleet of 23 conventionally powered submarines, and with at least four more of the advanced [*Taigei* class]() boats to be added in the future. ![]() *The first of Japan’s most advanced class of submarine, the *Taigei* is launched in October 2020 in the city of Kobe. Japanese Ministry of Defense* At this point, we don’t know the relationship between the sub-launched missile and the Type 12. However, work on an extended-range version of the Type 12 began back [in the 2018 fiscal year](). The redesigned missile has enlarged flying surfaces, a more efficient powerplant, and additional fuel. In this way, the 124-mile range of the baseline Type 12 will be extended to 560 miles, and, later, up to 930 miles. Even the first version of these would roughly correspond to the requirements for the sub-launched missile. Other changes in the improved Type 12 include a land-attack capability and radar cross-section reduction measures. Taken together, all these developments also reflect Japan’s concerns about the threat it faces from a [rapidly growing fleet]() of Chinese surface warships. People’s Liberation Army Navy (PLAN) activity in the waters around Japan and in the [South China Sea]() and the [East China Sea]() has steadily increased. ![A rare Chinese naval drill with a previously unannounced live-fire component has disrupted air traffic over and around the Tasman Sea between Australia and New Zealand.]() *A Chinese People’s Liberation Army Navy Type 055 destroyer. *via Chinese internet* Chinese Navy* The East China Sea is also the scene of a long-running dispute over ownership of [an uninhabited island chain](). Tensions here have also grown in recent years, including patrols by PLAN aircraft carriers. The area is referenced in the latest defense white paper: “The existing order of world peace is being seriously challenged, and Japan finds itself in the most severe and complex security environment of the postwar era. China has been swiftly increasing its national defense expenditures, thereby extensively and rapidly enhancing its military capability in a qualitative and quantitative manner and intensifying its activities in the East China Sea, including around the Senkaku Islands, and the Pacific.” When it comes to land-attack capabilities, this is also a very significant development for the JMSDF’s submarine fleet. The sub-launched land-attack cruise missile would be suitable for striking critical ground targets, including the proliferating [ballistic missile]() and [nuclear capabilities]() in North Korea. Pyongyang has repeatedly [launched ballistic missiles]() capable of reaching Japan into waters off that country. At the same time, a long-range cruise missile of this kind would be able to strike critical military and leadership infrastructure, as well as airbases and air-defense sites, during a conflict. Compared to other means of delivering strikes on critical land targets at great distances, a sub-launched cruise missile is much more survivable. It would provide Japan with a counterstrike capability, even if many of its aircraft and surface combatants had already been knocked out by an enemy’s first strike. ![]() *A diagram entitled *Future Operation of Stand-off Defense Capabilities* from the 2025 Defense White Paper. *Japanese Ministry of Defense** The efficiency of such a weapon would be enhanced by the advanced nature of the JMSDF’s most recent submarines, including a propulsion system [based on lithium-ion batteries]() in the newest examples. This ensures that the submarines are notably quiet and hard for an adversary to track. Until this new capability is fielded, JMSDF will have an interim long-range missile capability, in the shape of the U.S.-supplied Tomahawk cruise missile. A first [purchase of Tomahawk cruise missiles]() is something we reported on back in 2017. Japan’s Ministry of Defense has described the Tomahawk plan as a crash program to supplement its efforts to locally develop new standoff missiles. Once fielded, the Tomahawks will enhance “standoff defense capabilities in order to intercept and eliminate invading forces against Japan at a rapid pace and at long range.” A total of 200 [Tomahawk Block IV]() and 200[ Tomahawk Block V]() missiles are planned to be delivered between Japan’s fiscal years 2025 and 2027. ![]() *A diagram showing the capabilities of JMSDF Aegis destroyers, including future Tomahawk and upgraded Type 12 missiles. *Japanese Ministry of Defense** The Block IV Tomahawk [can strike targets]() at a range of almost 1,000 miles, carrying a 1,000-pound unitary warhead. Meanwhile, the Block V Tomahawk is [an improved version]() that can also be used to hit moving targets, including enemy warships. The first Japanese warship destined to receive a Tomahawk capability recently sailed to the United States for the required modifications, as you read about [here](). ![]() *The JMSDF destroyer *Chokai* departs Yokosuka Base on September 27, 2025, headed to the United States for Tomahawk modifications. *JMSDF** Ultimately, the JMSDF will field the Tomahawk on all eight of its currently fielded Aegis destroyers and its two [Aegis System Equipped Vessels]() (ASEV), but there are no plans to put it on its submarines as of yet. It should also be noted that Japan is [acquiring air-launched cruise missiles ]()for land-attack missions, too. Clearly, expanding its standoff missile capabilities, for both land-attack and anti-ship missions, is a priority for Japan right now. The latest contracts ensure that its submarines and surface warships will be very much at the spearhead of this new-look, more offensive posture. *Contact the author: thomas@thewarzone.com* ## Author Thomas Newdick is a staff writer at *TWZ*, where he covers military aviation, defense technology, weapons systems, and international security. Based in Berlin, Germany, he reports on conflicts, military modernization efforts, and emerging aerospace technologies around the world, with a particular interest in airpower and its role in contemporary warfare. His reporting is informed by deep expertise in modern and historical airpower, particularly in Europe, with a focus on military aviation, air campaigns, and aerospace developments across the continent and beyond. Over a journalism career spanning more than 25 years, Thomas has become known for making complex defense and aerospace topics accessible to a broad audience. His reporting combines technical expertise, historical context, and a focus on the real-world operational and strategic implications of military developments. ### Author social links [Twitter]()